If it’s as bad a ride as the OP has stated, then I feel it’s something beyond simple adjustment, though no one has mentioned the setting of the shockers. Could it be that they have been set to the hardest setting?
If that is not the culprit, then If it were mine, I would have each suspension leg completely dismantled to check the bushes and to make sure that all the components have been assembled in the right places…and preferably by a Morgan technician who knows what he is doing.